Elysia bangtawaensis
Green sea slugs (Elysia bangtawaensis) are occasionally present in mangrove creeks in Australia. In fact these sea slugs have only once before been recorded in Australian waters and were originally found in Thailand. They eat algae but rather that just digesting the algae, they strip out the alga’s chloroplasts and keep them alive in tubes running from their stomach. The sea slugs become a green photosynthesizing animal that looks similar to a mint leaf and which can live for up to a year on photosynthesis alone. Although similar to sea slugs, nudibranchs are predators. More information about this species can be located at the Sea Slug Forum.
These sea slugs were observed during a personal project to document mangroves in Cairns region of Australia to see if mangrove zones are moving in relation to sea level rise. This project uses a large collection of georeferenced images to monitor events such as mangroves establishing in areas that are currently saltpans.